(1) Field of the Invention
This invention is directed toward open ended wrenches, in particular, to wrenches that incorporate elements and features that are useful for allowing a wrench to loosen/tighten a bolt (or nut) without removing the wrench from the fitted position on the bolt.
(2) Description of Related Art
Wrenches are useful for a variety of tightening or loosening situations when applied to nuts and bolts, and some are designed to provide a ratcheting effect. However, open ended wrenches are not easily configured to a ratcheting method, and it is difficult to incorporate a ratcheting method that is also reversible into an open ended wrench.
For example, U.S. Pat. No. 4,574,665 teaches the use of an open end wrench along with multipoint cylinders around the perimeter of a bolt that is being loosened. The cylinders rotate about an offset axis, and recess between two chambers around the perimeter of the bolt for the ratchet effect. In one chamber, i.e., the tighter tool—bolt chamber clearance, the torque is applied. In the other chamber, the cylinder recess when the wrench is reversed in direction. This offset rotation is undesirable when the rotating cylinders bend, as may be caused by an applied user torque, which will cause the wrench to fail as the cylinders may fail to reposition. Also the cylinders tend to engage the bolt at the corners or points, which are often rounded, and is a less reliable method of rotating a bolt. U.S. Pat. No. 2,550,010 has similar cylinder features and has similar concerns.
It is desirable to incorporate a reversible feature for an open end ratchet wrench, as it is also frequently the case where a wrench is put on a nut only to discover that the bolt must be turned in the other direction. This occurs when the bolt is at an awkward position with respect to the user of the wrench, and where it is not instantly obvious which way the bolt should be turned. A reversible feature prevents the need for the user to remove the wrench and re-insert it back on the bolt, simplifying the task of loosening or tightening.